Aah thanks for the pointers! I probably won't bother with the 31t until mine is worn, but I might look into that HG61 you mentioned! Not a bad price and will provide about 5% more torque for longer climbs! With a 31t front that would be another 3% and would overall be closer to a 9% increase in available torque. If I went that would I would probably keep 6 gears on the rear.